17-bromo steroid adducts



Patented Dec. 9, 1952 UNITE mszsr- PATENT era-CE new v ii-eaom o s'riiao n ADDUCTS V RobertH. Levin, A Vern McIntosh,

George B. Spero, Kalamazoo, Mich, assignors to The .Upjo,hn..Company, Kalamazoo, Mich., a

corporation of Michigan No Drawing. Application September 12, 1950,

4 basis; (01. ace-4:39.55)

The present invention relates to adducts''' of 17-bromo3acyloxy-.5,'7,9(11)--pregnatrien 20-ones with certain dienophilic'acidsfianhy drides, andesters, and to a process for the production thereof. The compounds of the-presentinvention may be represented by the structural'forniula:

CH3 c= o wherein Ac is the residue of an organic carboxylic acid, especially those containing from-one to eightcarbon atoms, inclusive; and A is the adduct radical of a dienophile selected from the group consisting of maleic. .acid, .maleic anhydride,and maleic acid diesters containing from.

one to eight carbon atoms, inclusive, in the esterifying group. c It is an objectofthe present invention'vto pro-;

vide a novel group of compoundslwhich areiuseeful in the preparation of. steroid compounds con-:1

taining an oxygen atom at. carbon :atom eleven.

Another object oithe inventionis theprovision of apr cess for the productionofthe novel come pounds, (11)-pregnatrien:ZQ-ones. Other objects of the invention will become apparent hereinafter.

The compounds of the present invention, as I previously stated, arecuseful in the preparation of steroid compounds having an oxygen atom attached to carbon atom eleven, Such compounds are of particular interest in the; field of, q steroid research due to the biological-activity of the cortical hormones and certain known derivatives thereof, which o rygenated steroidsare known to have biological efiectsdifieringmarkedly from the 'unoxygenatedsteroidsr I;t; 15,]

therefore, of importance to investigatethe oxy genated derivatives of such adducts, particularly:

those oxygenated as to investigate at carbon atom eleven, as well; the biological activity; eithe adducts themselves and their 1 transformation products Theimportance of suchiinvestigation is moreover emphasized by the acuteshortage 017 adrenal cortical hormones, ia'n'd the a ess; of any present suggestion,foralleyiation otthesaid shortage except through organic synthesis.

Novel compounds of the present invention which are of particular interest are those coma pounds of the'abovegenericformula wherein AcO represents an ester of the-3-hydroxy group with a carboxylicgacid containing up to and ineluding. eight carbon atoms. Among theacids whichcan be-used are formic, acetic, propionic,-

butyric, Valerie, hexanoic, heptanoic, octanoic,; succinic, glutaric, cyclopentanoic, cyclohexanoic,- benzoic, toluic, and the like. Preierredacids are The acids may also" the lower-aliphatic acids. contain sub'stituentasuch as halo, alkyl, and

methoxy, which are non-reactive-under the -reaction conditions employed. The adduct bridge (A- in such compounds may be represented by the graphic formula:

i-coon wherein R represents hydrogen or the organic residue of an alcohol. Such esters include the methyl, ethyl, propyl, isopropyl, butyl, isobutyl, lauryl, heptyl, octyl kcyclopentyl, cyclohexyl, benzyl, and the like esters. The esterifying radical may also contain non-reactive substituents, such as halo, methoxy, or hydroxy, if desired. While the esters of the maleic acid adduct are described herein with particular reference to the methyl esters, the preferred embodiment of R is a lower-alkyl radical containing from one to eight, carbon atoms,inclusive. Alternatively,- the a.

adduct may be depicted by the graphic formula:

which is representative of the maleic anhydride adduct. 1 r

The compounds of the invention are usually colorless crystalline solids. The acid and anhydride adducts are readily converted into diester adducts by esterification with conventional reagents such as the diazoalkanes [Wilds et al.,

3 J. Org. Chem. 13, 763 (1948) l. The dibasic acids may be converted into their corresponding anhydrides by heat.

The 17 -bromo-3-acyloxy 5,7,9(11) pregnatrien-20-one adducts of the present invention have the formula:

wherein A and Ac have the values previously given. These compounds are prepared by the selective bromination of the corresponding 3- acyloxy-5,'T,9(11) -pregnatrien--one adduct, to introduce a bromine atom thereinto at the 17 position, using about one mole of bromine, preferably a slight excess over one mole of bromine, per mole of starting steroid. The steroid is dissolved in acetic acid and a solution of the bromine in acetic acid is added portionwise thereto at a temperature between about zero and I C=C H-A cyloxy CH 3 I wherein A and Ac have the values previously given.

Adducts of 3,22-diacyloxybisnor-5,7,9(l1), 20(22) -cholatetraenes [22-enol esters of B-acyloxybisnor-5,7,9( l1) -cholatrien22-alsl are conveniently prepared by subjecting an adduct of a 3-acyloxybisnor-5,7,9(11)-cholatrien-22-al, of the formula:

CH-CHO CH3 l -Cu wherein A and Ac have the values previously given, to the action of an acid anhydride or an acid halide in the presence of an alkaline salt of the acid. The starting adducts of Z-acyloxybisnor-5,7,9(11)-cholatrien-22-als can be prepared from adducts of 3-esters of dehydroergosterol by selective oxidation as described and claimed in the copending application Serial 111,100 of Robert H. Levin, filed 1949 August 18, and as more fully described hereinafter.

The 3-esters of dehydroergosterol, from which the 3 acyloxybisnor-5,7,9(11) -cholatrien-22-al adducts are prepared, can be synthesized in several ways starting with ergosterol. For example, ergosterol can be transformed to dehydroergosterol with mercuric acetate according to known methods [Windaus et al., Ann. 465, 157 (1928)] and the B-hydroxy group of the dehydroergosterol acylated by known procedure. Alternatively the 3-hydroxy group of ergosterol can be acylated prior to the preparation of the dehydro derivative, a procedure which is particularly preferred in the preparation of the 3- acetoxy derivative. The adducts of dehydroergosterol are then prepared by the addition of maleic anhydride or the like to dehydroergosterol or a 3-ester thereof according to known methods [Honigmann, Ann. 508, 89 (1934) l. The anhydrides can then be converted to their corresponding acids and esters if desired.

The ester group, when present in the 3-position of dehydroergosterol, is for the purpose of protecting the B-hydroxy group in subsequent chemical reactions. For this purpose any convenient ester of an organic carboxylic acid, which is non-reactive under the conditions of the reaction, is suitable. The preferred acids are the fatty acids such as formic, acetic, propionic, butyric, valeric, hexanoic, heptanoic, octanoic; dibasic acids such as malonic, succinic, phthalic; cycloaliphatic acids such as cyclopentanoic and cyclohexanoic; and aromatic acids such as benzoic, toluic, naphthoic, and the like. The acids may also contain substituents such as halogen, alkyl, the methoxy radical, and the like, and these substituents will be carried throughout the synthesis. If desired, the acyl group can be changed to another acyl group by saponifying the ester to give a 3-hydroxy compound, which can then be re-esterified as previously described.

A preferred method for preparing some of the dehydroergosteryl adducts comprises the saponification of a 3-acyloxy adduct of dehydroergosterol with dilute alkali followed by acidification. The 3-hydroxy dicarboxylic acid thus formed can be converted to the B-hydroxy anhydride by heat, or it can be converted to any desired 3-acyloxy anhydride adduct by heating under reflux with the appropriate acid anhydride or chloride in pyridine solution. Dialkyl esters of the previously mentioned dicarboxylic acid adducts can be prepared by subjecting the acid to the action of an esterification reagent such as a diazoalkane [Wilds et al., J. Org. Chem. 13, 763 (1948) l, e. g., diazomethane, diazoethane, diazobutane, and the like.

The selective oxidation of an adduct of dehydroergosterol, or a 3-ester thereof, to produce an adduct of 3hydroXybisnor-5,7,9(11) -cholatrien- 22-al, or a 3-ester thereof, is accomplished by dissolving the dehydroergosteryl adduct in a suitable solvent, cooling to about minus eighty to plus thirty degrees centigrade, and passing ozone into the solution until about 1.0 to 1.25 moles of ozone per mole of adduct have been absorbed.

senate- Thetemperature of the solution shouldbe maina tai'ned'below plus thirty degrees Centigrade, pref-'- erably between a temperature of minus thirty and minus seventy degrees centigrade, during the addition of ozone, although temperatures as low as minus eighty and as high as plus thirty degrees centigrade are operative. The lower temperatures ofithepreferred range are readily obtained by cooling the solution of the adduct with a bath 01: solid carbon dioxide in acetone or the like;

although various other methods of cooling can 1 be used. Manyof the customary solvents usedin ozonizationsfsuch as chloroform, acetic acid; carbon tetrachloride, ethylene chloride, methylene are then decomposed under re;

that is, in the absence of oxidizing -agents, whether added or formed in the chloride, and the like,can be used.-

The "ozonides ducing conditions,

course of the-reaction byproducts of decomposition of the ozonide. This means that excess oxygen formed'by'decomposition of the ozon'i'de I isprevented froni'iorminghydrogen peroxide by combining with any Imoisture present, and

that'molecular oxygen is prevented from oxidizing th'ealdehyde thus formed This can be" conveniently accomplished by decomposing the; ozonide-in glacial acetic acid by the addition of finely-powdered zinc.

As is conventional with ozonizations when conducted in'sol vents, other than I glacial acetic acid, thesolve'nt used for ozonization is replaced, after" completion of the ozoni'zation,by addingglacial acetic {acid andremoving the lower-boiling sol vent by fractional distillation. Alternatively, the" solvent'can be removed by careful-warming under reduced pressure prior to the addition of glacial acetic acid, if desired.

After decomposition of the mov'al'o'f the zinc, the aldehyde can be recovered by diluting the acetic acid with Water, or in other conventional manner, such as by'formation "of an aldehyde derivative, e. g., the dinitr'op'henyl hydrazone,

Adducts of 3,22-diacycloxybisnor-5,7,9(11),- 20(22)-cholatetraenes [22-enol-esters of adducts of 3 acyloxybisnor-5,7,9(ll) -cholatrien-22-alsl can be conveniently prepared by heating the cor-.

responding 3-hydroxy' or 3-acyloxy aldehyde maleic acid,'ma1eic acid anhydride, or 'maleic acid ester addu'ct with a large excess of an organic carboxylic acid anhydridein the presence ozonide and 're-' of a 'smallamount of the alkali metal salt of the acid corresponding to the anhydride employed or anacid catalyst such as para-toluene sulfonic or sulfuric acid; The preferred anhydride is acetic anhydride, but other anhydrides, such as propicnic, 'butyric, valeric, hexanoic, and octanoic anhydrides, as well as benzoic acid anhydride, ortho-toluic acid anhydrida'and the like, are also operative. The acid anhydrides can also'be substituted by non-reactive groups, such as halo, alkyl} and methoxy, as in the case of chloro:

acetic, jortho toluic, or methoxybenzoic acid an hydrides The reaction can'be conveniently followedfbvobser'ving the color changes in the reactionmixture, optimum yields being obtained} by"dis continuing-'the application of heat when the color of the solution changes from-yellow to brown; Ordinarily the reaction is heated at about "140 degrees centigrade for from about four*-to six :hOUIS, but temperatures as low as 1G0 and as high as 180 degrees centigrade are also operative. The reaction is usually conducted at theboiling point of the anhydride, but in 'thei' case of the higher-boiling anhydrides'such as" s-hy'ar'o'xy' aldehyde 'adduct is thusreac'ted wi trol; "such as 'fdegreeseentigrade, mast" used, since the adduct otherwise "tends to decompose the higher temperature range. If

an, 'Ianhydride, the" hydr xy' 'jgr'oup wm' 'be acyl at'edf'and, similarly, it a maleicl acid adduct s used'instead of a diester or anhydride, the an hydride will be'formedl' The enol' es e b isolated by removing the excess anhydr deunder reduced pressure, and separating the'en ol ester from alkali metal salts, which procedureyields a, product sufficiently pure, for most purposes, but 1 which can be further purified by recrystallization from acetone-water, acetone-pentane, or like solvents, if desired.

The ,ozonization of the thus-prepared enol acylate to produce a 3-acy1oxy-5,7,9(11) -pregna,-,-, trien-ZQ-one adduct involves dissolvingthe enolv ester,v in a suitable solvent, cooling to about minus eighty degrees centigrade tojplus thirty degrees;- centigrade, and passingozone, ozonized' air, or. .1 ozonized oxygen into the solution until about 1.0., to about 1.25 moles. preferably 1.0 to 1.1 molesyfl of ozone per mole of adduct have been'ab'sorbed.

The addition of ozone to the 20:22 double bond is so rapid that only a small amount or ozone escapes from the reaction mixture, and .the amount of ozone ordinarily required therefore closely approximates the theoretical amount. Loss to the solvent, if any loss occurs, must be taken into consideration seventy de rees centigrade, duringthe addition of ozone, although temperatures as low as minus eighty and as high as plus thirty degreescentigrade areoperative. The'lower temperatures of the range are readily obtained by cooling the solution of the adduct with a bath or solid'carbon dioxide in ace one or the like, although variousf" other methods of cooling may be employed.-

Many of the customarysolvents used in, ozonizations, such as chloroform, methylene embrace; ethylene chloride, carbon tetrachloride, acetic acid, and the like, can be used for the ozonization reaction.

The 20:22 ozonides thus produced are then de-.

composed under conditions normally employed for decomposition of such compounds. This can conveniently be accomplished by decomposing the ozonide with hydrogen peroxide, by hydrolysis, by treatment with zinc in glacial acetic acid; 1 or by a catalytic amount of colloidal metal such as silver, platinum, or palladium in a solvent, such, 'j as glacial acetic acid, alcohol, or ethyl acetatef", in which latter case reductive conditions, e. g.,,a. hydrogen atmosphere,,are also employedflThe f use of reductive conditionsfis well established in theart [Hill and Kelly, "Organic Chemistry, page 53, The Blackiston Company, Philadelphia (1934) Church et al., J. Am. Chem. Soc, 56, 176- 184 (1934); Gilman, Organic Chemistry, Second Edition, page 636, John Wiley and Sons, New ifcqrli) (1943); Long, Chem. Reviews, 27, 452-454 As is conventional withdecomposition of ozonides with zinc, when the ozonizat-ions are'conducted in solvents other than glacial aceticacid, the solvent used for the ozo'nization is replaced,

after completion of the ozonization, by adding, glacial acetic acid and removing the lower-boil ing solvent by fractional distillation, 'or the solin calculating the" amount of ozone to be introduced. The temper ature of the solution should be main ained below' plus thirty degrees centigrade, preferably be-f' tween a temperature of minus thirty and minus vent can be removed by careful warming under reduced pressure prior to the addition of acetic acid, if desired. After decomposition of the 20:22 ozonide and removal of the metal, the ketone can be recovered by diluting the acetic acid with water, or by other conventional procedure for the recovery of ketones, such as by formation of a carbonyl derivative, e. g., the 2,4-dinitrophenylhydrazone. Recrystallization from acetone or the like results in a more highly purified ketone product.

The following examples are illustrative of the process and products of the present invention, but are not to be construed as limiting.

Pl-LEPARATlON 1.DI1\[ETIIYL MALEA'H; ADDUCT or DEHYDROERGOSTERYL BENZOATE PREPARATION 2.l)11ui:rnYL MALEATE ADnUcr or DEHYDROERGOSTERYL ACETATE In a manner essentially that described in Preparation l, the dimethyl maleate adduct of dehydroergosteryl acetate, melting at 177 to 179 degrees centigrade, was prepared from the dimethyl maleate adduct of dehydroergosterol and acetyl chloride.

PREPARATION 3.DIMETHYL MALEATE Aunuo'r or DEHYDBOERGOSTERYL FORMATE A solution of six grams of dimethyl maleate adduct of dehydroergosterol in fifty milliliters of 87 percent formic acid was heated under reflux for one hour, cooled, and the dimethyl maleate adduct of dehydroergosteryl formate filtered therefrom. Upon crystallization from acetone, the purified material melted at 177.5 to 178.5 degrees centigrade.

PREPARATION MALEIQ. A011) Answer 01' DEIIYDROERGOSTEROL A solution of 2.0 grams of sodium hydroxide in twenty milliliters of water was added to a solution of 1.73 grams of the maleic anhydride adduct of dehydroergosteryl acetate (M. P. 230-232 degrees centigrade) in forty milliliters of dioxane. The mixture solidified, but dissolved on addition of 300 milliliters of Water and heating to eighty degrees centigrade. After half an hour the solution was cooled and made acid with aqueous three normal hydrochloric acid, to give 1.61 grams of precipitate. On crystallization from a dioxanewater mixture, the inaleic acid adduct of dehydroergosterol melted at 190l92 degrees centigrade.

lhmmimriox 5.I\IALEIC Aa'nrnmns Aoouc'r or 3HEPTASOYLOXYDICHYDROERGOSTEROL The maleic acid adduct of dehydrcergosterol from Preparation 4 was dissolved in a mixture of seven milliliters of warm pyridine and fourteen milliliters of heptylic anhydride, and the mixture heated under reflux for one hour. About eighty percent of the reaction solvent was removed under reduced pressure, and the residue then dissolved in methyl alcohol. The methyl alcohol PREPARATION 6.-\L\L1c1c ANHYDRIDE ADDUCT or 3- mcr.l-.-lo1croxrmems-5,7,9(11) -CHOLATRlEN-22AL A solution of 5.35 grams of the maleic anhydride adduct of 3-beta-acetoxydehydroergosterol in 107 milliliters of methylene chloride was cooled to about minus seventy degrees centigrade and ozonized until 505 milligrams of ozone had been absorbed. The temperature of the solution was then gradually raised to about plus ten to fifteen degrees centigrade, whereupon seventy milliliters of glacial acetic acid was added and the methylene chloride removed under reduced pressure. Seven grams of zinc dust was then added to the cold solution at a uniform rate over a period of ten minutes, while keeping the reaction temperature below plus twenty degrees centigrade. After being stirred for fifteen minutes, the mixture was filtered and the filtrate poured into water. There was thus obtained 4.31 grams of maleic anhydride adduct of 3 beta acetoxybisnor 5,7,9(1l)-cholatrien-22-al, a fine white powder which melted at 187497 degrees centigrade.

To a solution of 0.30 gram of the maleic anhydride adduct of 3-beta-acetoxybisnor-5,7,9(l1)- cholatrien-22-al, in thirty milliliters of ethanol, was added twenty milliliters of alcohol contain ing one percent 2,4-dinitrophenylhydrazine and three percent concentrated hydrochloric acid. The mixture was allowed to stand for one hour at room temperature and then placed in a refrigerator to complete precipitation of the yellow crystals. The precipitate was then collected and recrystallized from a mixture of chloroform and alcohol, to give the 2,4-dinitrophenylhydrazone of the maleic anhydride adduct of S-beta-acetoxybisnor-5,7,9(1l) -cholatrien-22-al, melting at 269- 2'71 degrees Centigrade.

PREPARATION 7.-l\IALEIC ANHYDRIDE AnoUcr or 3- nIzTa-Aoirroxrmsxon-5,7,0 (11) -cnoL -x'rmEN-22AL A two-liter round-bottom flask was charged with fifty grams (0.93 mole) of dehydroergosteryl acetate maleic anhydride adduct and one liter of methylene chloride. The solution was cooled to Dry-Ice temperature with a trichloroethylene bath and ozonized oxygen passed through at a rate of 1200 milliliters of oxygen per minute (at this rate the ozonizer Was producing about 36 milligrams of ozone per minute). The flow of ozonized oxygen was maintained for 128 minutes, a total of 4608 milligrams (105 percent) of ozone being passed into the solution. The reaction mixture was transferred to a two-liter, roundbottom flask fitted with a capillary and a condenser for downward distillation, 300 milliliters of acetic acid added, and the methylene chloride distilled over in vacuo at forty degrees centigrade or below. The flask was then placed in a water bath and fitted with a stirrer. An additional 200 milliliters of acetic acid was added and the 020- nide decomposed by the addition of fifty grams of zinc dust. The zinc was added in portions over a period of twenty to thirty minutes while the solution was stirred and the temperature maintained at seventeen to twenty degrees centigrade. After addition, the mixture was stirred for another twenty minutes and then filtered. The precipitated zine dust was washed by filtering 100 milliliters of acetic acid therethrough, and the filtrate gradually diluted with .trien-.2 2,-al teryLmaleic acid adduct; and .3-aoyloxybisnor- .5,7,!)(11)-cholatrien-22-al maleic acid adducts ohlor 39 water (1 to 1200 milliliters) until the product had vbeendrowned out. The. product was then cooled in the refrigerator overnight and filtered.

The yield of crystalline product was 42 grams,

assaying 89-95 percent of the desired aldehyde.

PREPARATION 8 In a, manner essentially that described in Prep- ..aration 6, the following compounds were prev(3) Dimethyl maleateadduct of B-beta-benzoyloxybisnor-5,7,9 (1 1) -cholatrien-22-al, melting at 183-187 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 224=-2l9 degrees centigrade.

(4) Dimethyl maleate adduct of 3-oeta-acetoxybisnor-5,7,9(l1)-cholatrien-22-al, melting at 172-178 degrees centigrade, 2,4-dinitrophenylhydrazonamelting at 238.to 244 degrees centigrade.

..(5) Dimethyl .maleate adduct of B-hydroxy- .bisnor=5,7.,9(11) -cholatrien-22-al, melting at 163- 1'70. degreesv centigrade. 2,4-dinitrophenylhydra- :zone,.melting at 250-254degrees centigrade.

In. a manner similar .to the. above, the maleic ..anhydride adduct. of 3-hydroxybisnor.- 5,7,9(11)- l...cholatr,ien-22al is obtained from. dehydroer- .go'steryl maleic anhydride adduct; themaleic acid adduct vof ..3-hydroxybisnor.-5,7,9 (11) -cholais .obtained from dehydroergosare. obtained from the maleic acid adduct of v3,-acylOXydehydroergosterols.

PREPARATION 9.-Dh\iETHYL :MALEATE ADDUCT or I 3-.r1rn toXxBIsNoR-5j7 ,9 (11 oH0LATmnN-22- u.

.A solution of 2.69 grams (.005 mole) of the dimethyl ester of the maleic acidiadduct of dehydroergost erol, in eighty milliliters of methylene id'e, cooled by a Dry Ice and triohloroethylene bath, was treated with ozonizied oxygen until 247.36 milligrams (.0051 mole) "of ozone was absorbed. The solution was then allowed to warm "to"room...temperature, whereafter thirty milliliters of acetic acidwas added and. the methylene chloride removed in vacuo. While cooling in a water-bath. at fifteen degrees centigrade, four grams of Izinc dust were. added in portions with stirring, the temperature being maintained between fifteen and twenty degrees centigrade.

. Stirring was continued for another fifteen'minutes -whereafter the zinc separated by filtratio'n. The filtrate was diluted withwater to cloudines'sfextracted with ether, theether extract washed with sodium bicarbonate and then with w'ater to neutrality, the solution then dried over'sodium sulfate and evaporated to dryness in vacuo'. The residue was crystallized from acetic acid and water, giving 1.92 grains (81.5 percent of the theoretical), melting point 91-97 degrees centig radefwhich yielded a dinitrophenylhydrazone derivative 'in 72.5 percent yield, melting" point 212-238 degrees centigrade. The

, aldehyde was recrystallized and found to have a purifiedmeltingpoint of 163-170 deg1'ees' centigrade, while the dinitrophenylhydrazone.deriva- .grade. from a mixture of acetoneand pentane raised tive was recrystallized until a meltingpoi-nt. of 250-254 degrees centigrade (was attained.

A mixture of twenty grams of the maleio anhycride adduct of 3beta-acet0Xybisn0r-5,7,9(11)- cholatrien-22-al, six grams of anhydrous sodium acetate, and 600 milliliters of acetic, anhydride, was heated under reflux for six hours, whereaiter volatile components were removed under reduced pressure. The resulting solid was digested with five fifty-milliliterIportions 0f..boiling acetone for five minutes .each,.'and the .extracts combined and diluted with milliliters of water. There was thus obtainedsixteengrams of the maleic anhydride adduot'of 3-betaeacetoxy-22-acetoxybisnor 5,7,9 (11). ,20(22) cholatetraene, which melted at 186.130 .193 degn'eescenti- Recrystallization of the crude-product the melting point to 200.5 to 202 degreescentigrade.

PREPARATION 11 5,7,9(11) ,20(22) -cholatetraene adduc-ts, are ;ob-

tained from the compounds ofPrep arationsqfi l and 8. Such representative compounds include 3-formoxy 22-acetoxybisnor 5,7,9(11) ',20 (22)- cholatetraene, 3.-propionoxy 22 acetoxybisnor- 5,7,9 11) ,20 (22) cholatetraene, 3,22. dipropio noxybisnor 5,7,9 (11) ,20(22) -cholatetraene, 3,22- dibenzoyloxybisnor 5,7,9 (11) ,20 (22) cholatetraene, and 3-heptanoyloxy-22-octanoyloxybisnor- 5,7,?)(11) ,20(22) cholate tra ene :adductswitmmaleic anhydride or maleic. acid esters .suchasthe dimethyl maleate, diethyl maleate, dipropyl maleate, diisopropyl maleate, dibut-yl maleate,;-di octyl maleate, dibenzyl maleate, and the like.

PREPARATION 12.MALEI0 ANHYDRlDlt Annual, or l-BETA-AGirrOXY-dZQ 11) JREGNATRIEN-QO-QNE A solution of 5.08 grams of the maleic anhydride adduct of 3-beta-acetoXybisnor-5,7,9{11) oholatrien-ZZ-al enol acetatein iOOmilliliters of methylene chloride was cooled to about minus seventy degrees centigrade and ozonized until 4:83 milligrams of ozone had .been absorbed. Fifty milliliters of glacial acetic acid was then added and the methylene chloride removed un der reducedpressure. An additional thirty milliliters of glacial acetic acid was then added and the ozonide decomposed by adding seven grams of powdered zinc at a substantially uniformrate while maintaining the reaction temperature beveen seventeen and twenty degrees centigrade. The mixture was stirred foranv additional twenty inutes, filtered, and the zinc washed with PREPARATION 13.\IA'LEI0 Aon) ADDUCT or g-BETA- HYnRoxY-5,7 ,9 11 -PREGNATRIEN-20-ONE A solution of 4.52 grams (0.01 mole) of the maleic anhydride adduct of 3-beta-acetoxy- 5,7,9(ll)-pregnatrien-20-one, M. P. 263-2645 degrees centigrade, in a mixture of 100 milliliters of lA-dioxane and 400 milliliters of water containing four grams (0.10 mole) of sodium hydroxide was allowed to stand at room temperature for two and one-half hours, whereupon a small quantity of plate-like crystals formed. These were dissolved by heating the mixture to seventy degrees Centigrade for one-half hour. The reaction mixture was then made acid with fifty milliliters of three normal hydrochloric acid and refrigerated to give a precipitate of 3.05 grams of needle-like crystals melting at 173-17? degrees centigrade. On crystallization from a dioxane-water mixture, the compound melted at 211-215 degrees centigrade. The melting point was found to vary somewhat with the rate of heating.

PREPARATION 1-LDIMETHYL MALEATE OF I'IYDROXYEJQ (11) amuomarumw-QO-omc A suspension of 0.4 gram of the maleic acid adduct of 3 beta-hyd1'oxy-5,7,9(1l)-pregnatrien-20-one, in fifty milliliters of dry ether, was cooled in an ice-salt bath while a slight excess of diazomethane in methylene chloride was added over a 25-minute period with stirring. Ten minutes after addition was complete, the solution was placed on a steam bath and concentrated rapidly to dryness. The residue was crystallized from an acetone-water mixture to give 0.34 gram of the dimethyl maleate of 3-beta-hydroxy-5,7,9(ll)pregnatrien-20-one, melting at 193-195 degrees centigrade. After chromatography and recrystallization, the compound melted at 192-197 degrees centigrade.

In the same manner as given above, other dialkyl maleates, e. g., the diethyl, dipropyl, diisopropyl, dibutyl, and dioctyl maleates of 3-hydroxy 5,7,!)(11) pregnatrien-ZO-one are prepared from 3-hydroxy-5,'7,9(ll)-pregnatrien-20- one maleic acid adduct and the appropriate diazoalkane, or by other equivalent esterification procedure.

PREPARATION ]5.D1METHYL M'ALEATE F 8-BETA- ACETOXY-5,7,9 11 -1REGNATllIE-Zi-20-ONE 9m-,;;temperature, and poured into ice-water. 2513-1 1. M antim a iiectedzbaffiitrawi J a ri i 12 Analysis:

Calculated for CcsHaaOv C, 69.86; H,7.68 Found 69.81; 7.86 69.70; 7.62

By the same manner of esterification, the following C-3 esters were prepared: (1) dimethyl maleate adduct of 3-beta-formoxy-5,7,9(1l)- pregnatrien-20-one, melting point 223-230 degrees centigrade, and (2) the dimethyl maleate adduct of 3 beta benzoyloxy 5,7,9(ll) pregnatrien-ZO-one, melting point 250-254 degrees centigrade.

PREPARATION 16.Mxus1o Axnrmuou Aouucr or 3- BErA-HEPTANorLoxY-5,7,9 l1) -llll-IGNATRlEN-20-0Nl PREPARATION 17 MALEIC ANIIYDRIDE AnDUcT or 3-nE'rA-HYDR0xY-5,7,9 11 -PREGNATRIEN-QO-ON 15 Similarly, the maleic anhydride adduct of 3- beta-hydroxy-5,7,9(ll) pregnatrien 20 one, melting point about 195 degrees centrigrade, was prepared by refluxing the maleic acid adduct of 3-beta-hydroxy-5,7,9 (11) -pregnatrien-20-one with Dowtherm for eight hours. The 3-hydroxy maleic anhydride adduct is also obtained by heating the 3-hydroxy maleic acid to just above its melting point, which procedure causes water to be evolved, with the closing of the anhydride ring.

In the same manner as given above, still other 5,7,9(ll)-pregnatrien-20-one adducts are prepared from the corresponding 3,22-diacyloxybisnor-5,7,9( ll) ,20 (22) -cholatetraene maleic acid, maleic acid anhydride, and maleic acid diester adducts. Such compounds include the 3-formoxy-5,7,9(l1)-pregnatrien-20-one maleic acid, maleic acid anhydride, dimethy maleate, diethyl maleate, dibutyl maleate, dioctyl maleate, diisopropyl maleate, dibenzyl maleate, and the like adducts; the corresponding 3-propionoxy, butyroxy, valeroxy, hexanoyloxy, heptanoyloxy, octanoyloxy, benzoyloxy, and similar 20-ketone adducts, including, for example 3-propionoxy-5,7,9 (11) -pregnatrien-20-one dipropyl maleate, 3-benzoyloxy-5,7,9(11) -pregnatrien 20 one dibenzyl maleate, 3 heptanoyloxy5,7,9( 11) -pregnatrien- 20-one dimethyl maleate, 3-valeroyloxy-5,7,9 (l1)-pregnatrien-20-one maleic acid anhydride adducts, and the like.

Example 1.Maleic anhydride adduct of 3-betaacetozcy 1? bromo 5,7,9(11) pregnatrien- 20-one To a solution of 0.45 gram of 3-beta-acetoxy-5,'7, 9(11) -pregnatrien-20-one maleic anhydride adduct in fifteen milliliters of acetic acid was added 180 milligrams of bromine in five milliliters of acetic acid. The solution was allowed to stand at room temperature for 36 hours and was then poured into ice-water. The resulting crystalline material was recrystallized once from acetonewater and gave 0.35 gram of 3-beta-acetoxy-l7- ,bJr n QQ Q(lll-pregnatrien-ZO-one maleic an- -fidgt tie lifil amel i lgaatvlQae iwdcgeeesrenti- .aeees -i n'meporew cie tallizatiens afmmzaicetlme esulted inga final meltingpoint .Qffp202t- 205d112- e? centrigra' gqompqundmhaseban tirii a ls lfg ifniuseeee ideelzeesiifiohiotoflimri.

13 Analysis:

Calculated C, 61.02; H, 5.88; Br, 15.04 Found-Quinn. 61.05; 6:14; 15.20 61.35; 6.01; 15.56 14.76 14,74

Easamzale 2.-Dimethyz maleat adduct 3-betaa'cetory 17 bromo 5,7,9(11) pregnatrien- "205cm To a solution of 0.92 gram of 3-beta-acetoxyl'l-bromo-Sjlfii 11 -pregnatrien one maleic anhydride adduct in five milliliters of methylene chloride and m illiliters of methanol, cooled in an ice bath, was added '75 milliliters of a shammethane inmethylene chloride solution. The diazomethane solution-was added in 25-milliliter portions five minutes apart. The whole was allowed to stand in the ice bath for'two hours and at room temperature overnight. The solutionwas concentrated to 25 milliliters and was cooled. The dimethylmaleate adduct of 3-betaiacetoxy l'l-bromo 517,9(11) pregnatrien -20- ione '(Q.80 gram, melting point 235 242. degrees centigrade with decomposition) crystallized and was; filtered. Recrystallization from" acetonemethylene chloride resulted in a pure sample,

melting point 233-237 degrees centrigrade with decomposition.

Example 3.-Dimethyl maleate adduct of 3-beta- 1 benzoyloxy-N-bromo 5,7,9(11) pregnatrz'en- 20-one In the same manner as given in the above examples, the dimethyl maleate adduct of 3-betabenzoyloxy-17-bromo-5,7,9(11)-pregnatrien 20- one is prepared from the dimethyl maleate adduct of 3-beta-benzoyloxy-5,7,9 (11) -pregnatrien- 20-one.

Other adducts of the present invention include, for example, the maleicacid, maleic anhydride, dimethyl maleate, dieth'yl maleate, dipropyl maleate, diisopropyl maleate, dibutyl maleate, diamyl maleate, dihexy-l maleate, 'diheptyl maleate,

dibenzyl maleate, anddioctyl maleate adducts of 3 -formoxy, '3-acetoxy,j B-propionoxy, 3-'but'yroxy, 3-valeroyloxy; 3-hexanoy10xy;*3-heptanoyloxy, 3-

octanoyloxy, 3-benzoyloxy and like 3-acyloxy-17- bromo-5,' 7,9(l1) 'pregnatrien' -'"20 ones,"allof which are prepared as indicated above from the corresponding 3 acyloxy-5-,7 ,9 (11) -pregnatrien- ;20-one adduct.

Asstated in the foregoing, the compounds of the present invention are extremely useful in the preparation of other steroid compounds of interest and; importance per se as therapeutics, as well maleic anhydride, and 'maleic acid diesters, and

AcO'has' the same value as g ven previously.

" The preparation of the 17-bromo-3-acyloxy9,- 11-oxido-5,'7-pregnadien-20-one adducts involves .the oxidation .of the; corresponding 3-acyloxy- 5,7,9'(11) -preg natrien -20-one adductusing anorganic peracid or concentrated hydrogen peroxide as the-oxidant; Hydrogen peroxide is usually 5 when. the oxidant is hydrogen peroxideis glacial as in the preparation of still other steroids "having an oxygen atom at the eleven carbonf'as'in the adrenal cortical hormones. For example, the compounds of the invention are usefulas starting materials for the preparationpf 9;1l=oxido derivatives of the formula:

wherein A is the adduct radical of a dienophile selected from the group consisting of maleic acid,

1 action medium,

employed in the formof a twenty to ninetypercent: by weight aqueous solution, a thirty percent solution being preferred. The reaction is carried out by stirringthe adduct and oxidant together,

preferably in anorganic medium which is'nonreactive under the reaction conditions. Suitable media includechloroform, carbon tetrachloride,

mixtures of eher and chloroform, glacial acetic acid, and many others. Th ratio of oxygenfurn ishing agent to steroid can be variedconsiderably within broad ranges. Ratiosioiupto twenty moles to one are operative, butratios of from one to four moles per mole'ofsteroid are preferred for attainment of optimum yields, the exact ratio being preferably variedinve'rsel'y'with the reaction time desired to be employed. The

1 temperature of the mixture is usually maintained fatfrom about zero, degrees to about I'OOdegrees *cen'tigrade for a suitable period, e. g., from about one-halft twenty-four hours, depending on the concentration" of oxygen-furnishing agent, and

'the 9,11-oxido compound then isolated in any convenient manner, such as by volatilizing'the reextracting the residue with chloroform,'filtering;' volatilizing the chloroform, and recrystallizingthe residue from'an organic solvent. Alternatively, the compounds'may be rec'overedby pouring the reaction'product into water,1filtering.the solution, and drying the precipitate The 9,11-oxido compound is'usually-Iobtained in ajstate of high purity after'one or two recrystallizations. A convenient reaction medium acetic acid, and, when such is employed, the 9,1 1- oxido compound'is separated readily by pouring the reaction'pro'duct onto cracked ice to precipitate the 9,11-oxido compound, filtering, andrecrystallizing the dried'c'rude product, ejgf, from ethyl acetate.

Emample A.-Maleic anhydride adduct of 3-betaacetoxy-17-bromo-9,Z1 -oxido-5,7 p regnadien- ZO-cne Ten grams of 3-beta-acetoxy-9,11-oxido-5,7-

pregnadien-20-one maleic anhydride adduct was dissolved in 200 milliliters of acetic acid by warming and the solution then cooled to room temperature. Four milliliters of a bromine-acetic acid solution, having a 1'72'milligram per milliliter concentration, was added and the mixture allowed to stand. After twenty minutes the bromine color had disappeared. Seventeen additional milliliters of brominesolution was then added in portions as r 'apidly asthe bromine was taken up. The

solution was allowed to standfor'thirty minutes ,andit was then poured into l200,, milliliters.1of water. The resulting crystalline 3 -betaeacetoxy- 1'7 promo Q,ll-oxido 5,'7 -pregnadien:20-one;maleic anhydride adduct (11.6 grams, melting point 192-196 degrees centigrade) was isolated byJfil- 'ti'ation. Recrystallization from acetone yielded mater-19.1'fmeia'ng at 193-496 degrees centigrade,

To a solution of 355 milligrams of 3-beta-acetoxy-17-bromo-9,l1-oxido-5,7-pregnadien-20 one maleic anhydride adduct in ten milliliters of methylene chloride and forty milliliters of methanol, cooled in an ice bath, was added fifty milliliters of a solution of diazomethane in methylene chloride in 25-milliliter portions, fifteen minutes apart. The mixture was allowed to stand in the ice bath for two hours and was then concentrated on the steam bath until crystallization began. After cooling and filtering, there was obtained 250 milligrams of crystalline 3-beta-acetoxy-17-bro1no-9,l1-oxido-5,7-pregnadien 20-one dimethyl maleate adduct, which, after three recrystallizations from acetone-methylene chloride, melted at 239-2405 degrees centigrade, [alphal of minus 34.3 degrees in chloroform.

Analysis:

Calculated for C29H370sBr C, 58.68; H, 6.28; Br, 13.47 Found 58.82; 6.25; 13.68 58.88; 6.32; 13.38

The same compound is prepared by the seventeen bromination of 3'beta-acetoxy-9,1l-oxido- 5,7-pregnadien-20-one dimethyl maleate adduct, according to the method of the preceding example. Still other 3-acyloxy-l7-bromo-9,1l-oxido- 5,7-pregnadien-20-one adducts which are prepared in the same manner as iven above include the 3-beta-acetoxy 17 br-omo 9,11-oxido-5,7- pregnadien-20-one maleic acid adduct, as well as 3-formoxy, 3-propionoxy, 3-butyroxy, 3-valeroyloxy, 3-hexanoyloxy, 3heptanoyloxy, 3-benzoyloxy and 3-octanoyloxy 17 bromo 9,11-oxido-5,7- pregnadien-ZO-one maleic acid adducts, maleic anhydride adducts, dimethyl maleate, diethyl maleate, dipropyl maleate, diisopropyl maleate, dibutyl maleate, diamyl maleate, dihexyl maleate, diheptyl maleate, dibenzyl maleate and dioctyl maleate adducts, and the like:

These 9,11-oxido-17-bromo adducts are converted readily into 16,17 dehydro compounds, of the formula:

A AcO d wherein A and Ac have the values previously assigned, The 3-acyloxy 9,11 oxido-5,7,16(17) pregnatrien-ZO-one adducts are prepared from the corresponding l7-bromo compound by dehydrobromination, which is accomplished by heating the 17-bromo compound in pyridine, e. g., at about reflux temperature, recovering the reaction product by quenching the reaction in ice-water or in other conventional manner, and crystallizing the desired 3-acyloxy-9,l1-oxido-5,7,16(17)-pregnatrien-20-one adduct from an organic solvent or solvent pairs, if desired. Representative values of A in the above formula include, for example, formoxy, acetoxy, propionoxy, butyroxy, valeroyloxy, hexanoyloxy, heptanoyloxy, benzoyloxy, octanoyloxy, and the like, while the radicals rep- 16 resented by A include those of maleic acid, maleic anhydride, and dimethyl, diethyl, dipropyl, diisopropyl, dibutyl, diamyl, dihexyl, diheptyl, dibenzyl, and dioctyl maleates, and the like.

Example C.MaZeic anhydride adduct of 3-betaacetoary-QJ1-oa:ido-5,7,1G-pregnatrien-ZO-one A solution of 0.5 gram of 3-beta-acetoxy-l7- bromo-9,1l-oxido-pregnadien-ZO-one maleic anhydride adduct in fifteen milliliters of pyridine was refluxed for one hour, cooled, and poured into fifty milliliters of ice-water. The resulting yellow solid (0.27 gram, melting point 265-275 degrees centigrade) was crystallized from acetone-hexane to give 183 milligrams of 3-betaacetoxy 9,11 oxido 5,7,l6-pregnatrien-20-one maleic anhydride adduct, having a melting point of 267-272 degrees centigrade. Ultraviolet and infrared analysis showed the presence of the alphabeta-unsaturated ketone system.

In the same manner as given for the preparation of the 3-acyloxy-9,l1-oxido-5,7,l6(17) -pregnatrien-ZO-one adducts from 17-bromo-3-acyloxy-9,11-oxido-5,7-pregnadien-20-one adducts, 3- acyloxy-5,7,9( 11),16( l7) pregnatetraene-ZO-one adducts are prepared from the corresponding 17- bromo compounds. These 3-acyloxy-5,7,9(11), 16(17)-pregnatetraene-20-one adducts have the formula! I CH: 1 =0 CH3 l)- AcO wherein A and Ac have the values previously assigned. Representative values for A00 in the above formula are, for example, formoxy, acetoxy, propionoxy, butyroxy, valeroyloxy, hexanoyloxy, heptanoyloxy, benzoyloxy, octanoyloxy, and the like, while values of A include the adduct radicals of maleic acid, maleic anhydride and the dimethyl, diethyl, dipropyl diisopropyl, dibutyl, diamyl, dihexyl, diheptyl, dibenzyl, and dioctyl maleates.

It is to be understood that the invention is not to be limited to the exact details of operation or exact compounds shown and described, as obvious modifications and equivalents will be apparent to one skilled in the art, and the invention is therefore to be limited only by the scope of the appended claims.

We claim:

1. A l7-bromo 3 acyloxy-5,7,9(1l) trien-20-one adduct of the formula:

-pregnawherein Ac is the residue of an unsubstituted oranic monocarboxylic acid containing from one to eight carbon atoms, inclusive, and wherein A 17 is the adduct radical of a dienophile selected from the group consisting of maleic acid, maleic anhydride, and lower-alkyl diesters of maleic acid wherein the esterifying groups contain from one to eight carbon atoms, inclusive.

2. 17 bromo 3 acetoXy-5,7,9(ll) pregnatrien-ZO-one maleic anhydride adduct.

3. l7 bromo 3 acetoxy 5,7,9(11) pregnatrien-ZO-one dimethyl maleate adduct.

4. A compound of claim 1, wherein A00 is the acetoxy group.

ROBERT H. LEVIN. A VERN MCINTOSI-I, J R. GEORGE B. SPERO.

18 REFERENCES CITED The following references are of record in the file of this patent:

Number UNITED STATES PATENTS Name v Date Marker Feb. 6, 1945 

1. A 17-BROMO -3- ACYLOXY-5,7,9(11)-PREGNATRIEN-20-ONE ADDUCT OF THE FORMULA: 